Service cord fitting and connector

ABSTRACT

A service cord fitting and coupling having solderless means cooperating to hold the parts assembled and to complete an electrical connection between insulated conductors and both the male and female electrical contactors.

United States Patent 1 Clark 1 July 31, 1973 3,148,930 9/1964 Healy 339/219 R FOREIGN PATENTS OR APPLICATIONS 219,681 3/1958 Australia 339/88 C OTHER PUBLICATIONS IBM Technical Bu lletin, Panaro, Vol. 3, No. 6, 11/1960, p. 6.

Primary Examiner-Joseph I-I. McGlynn Attorney-W, D. Sellers et a1.

[57] ABSTRACT A service cord fitting and coupling having solderless means cooperating to hold the parts assembled and to' complete an electricalconnection between insulated conductors and both the male and female electrical contactors.

11 Claims, 4 Drawing Figures SERVICE CORD FITTING AND CONNECTOR This invention relates to service cords, and more particularly toseparable connectors and couplings featuring solderless means for connecting fully insulated conductors to the metallic conductors while simultaneously anchoring the parts assembled.

The service cord fitting of this invention is particularly suitable as a replacement for a damaged original connector plug. It is commonplace today for original equipment to be furnished with connector fittings molded to the service cord itself with the conductor terminals inaccessible for servicing. Should the original plug become damaged or unserviceable for any reason a problem is presented in replacing the damaged fitting with a new one in a simple and reliable manner. Not only is it necessary to cut off the original fitting but considerable expertise is customarily required to remove the insulation from the original conductors except at the cost of considerable time and effort and the risk of damaging the conductors.

These and other disadvantages are avoided by the present invention wherein any novice can replace the damaged fitting with a high quality, low cost substitute fitting with a minimum of effort and time and without need for removing the insulation from any conductor or need for making a soldered connection. To this end there is provided by this invention a service cord fitting having a non-conductive main body provided with metal screws effective as they are tightened to anchor the fitting contactors rigidly to the main body while at the same time cutting through the conductor insulation and into the conductor wire to make contact therewith while simultaneously anchoring the several parts assembled. The principles of the invention are equally suitable for use on both male and female coupling parts and irrespective of whether these are of the conventional or twist lock construction. Equalized strain on the cord conductors is assured by simply cutting all conductors off at the same length and then inserting them fully into a respective one of the conductor seating wells.

Accordingly, it is a primary object of the present invention to provide a new and improved service cord fitting and connector having common means for holding the parts assembled as well as completing an electrical connection between the insulated conductor and the fitting contactor.

Another object of the invention is the provision of a service cord fitting having simple, easily completed solderless means for effecting electrical and mechanical connections between the conductor and the fitting parts.

Another object of the invention is the provision of a separable connector for service cords all parts of which are held together by common means serving to provide a mechanical and an electrical connection between the parts and the service cord conductors.

Another object of the invention is the provision of a simplified service cord fitting for making solderless connections between the conductors and the fitting contactors without need for removing any insulation from the wires and for assuring that the strain on each conductor will be equalized on completion of the assembly.

These and other more specific objects will appear upon reading the following specification and claims and upon considering in connection therewith th e 'at tached drawing to which they relate.

Referring now to the drawing in which a preferred embodiment of the invention is illustrated:

FIG. 1 is a perspective view of aservice cord connector before the two fittings are coupled together;

FIG. 2 is a cross sectional view on an enlarged scale of the male fitting with the cover cap detached;

FIG. 3 is a fragmentary cross sectional view on an enlarged scale taken along line 3-3 on FIG. 1; and

FIG. 4 is a fragmentary cross sectional view on an enlarged scale of a second embodiment of the invention showing a twist lock connector fully assembled.

Referring initially more particularlyto FIGS. 1-3, there is shown one preferred embodiment of the invention, designated generally 10, comprising a service cord connector including a female fitting 11 and a male fitting 12 each assembled to a respective portion of a flexible service cord 15. The main body 16 of fitting 12 is formed of non-conductive material such as a tough, molded plastic. As here shown, fittings 11,12 are designed for use in a service cord having a ground wire connected to a male contactor 18 having a telescopic fit with a suitably shaped female grounding contactor, not shown, but understood as aligned with opening 19 in fitting 11.

The internal construction of the main body is best shown in FIG. 3 and includes a threaded well 20 for each of the contactors I8, 22, 23. Each of these contactors includes a right angle tang 25 provided with a perforation or tapered hole 26 (FIG. 3) seating a metallic screw 27. Screw 27 is formed with a sharp-edged V- shape hardened thread 28 one end of which merges with a flaring head generally complemental in shape with the flaring opening 26 through tang 25. As will be readily apparent from FIG. 3, when screw 27 is fully I tightened the flaring head bottoms against the flaring opening 26 and anchors male prong 23 rigidly and immovably in assembled position in main body 16.

A second well associated with each threaded well is inclined acutely to the axis of the threaded well with its lower inner end opening through the sidewall of the threaded well. Wells 30 are sized to have a snug fit with one of the insulated service cord conductors 32. Insulation 33 need not be removed from the conductor proper 34 which may be either twisted or a solid wire. The two wells and the associated screw thread are designed for use with conductor wires of a particular type and size and coated with insulation of a particular thickness to the end that the hardened sharp crest of the thread will cut through the insulation and penetrate into the conductor at several points along the side of the conductor to assure both a firm mechanical anchorage and a highly reliable electrical contact between the conductor and the screw. These objectives are assured simply by tightening the screw until the metal contactor 23 is firmly anchored in place.

Each half of the service cord connector includes an end cap 35 held assembled to a respective main body by a pair of screws 36. It will be understood that a suitable strain relief is preferably incorporated in the end cap or attached to the cord itself so as to bear against its interior after installation of assembly screws 36.

Referring now to the lower portion of FIG. 3, it will be understood that female fitting 11 includes a main body 38 constructed similarly to the male fitting just described except that its interior is enlarged and proevided with recesses enclosing the U-shaped female contactors 39. Each of these includes an L-shaped tang 40 constructed similar to tangs 25 of the male contactors and held assembled to the main body 38 and to the service cord conductors in the same manner described above in connection with male fitting 12. The end of housing 11 has openings 19, 41, 42 positioned to retherewith to receive one of said screws, and the outer ceive the male contactors18, 22, 23. Aligned with each of the openings 19, 41, 42 are respective female contactors similar to contactors 39 shown in FIG. 3. After the conductors and contactors have been assembled in the same manner described above, end cap 44 is secured in assembled position by screws 45.

Referring now to FIG. 4, there is shown a second modification constructed substantially identically with that just described in connection with FIGS. l-3 but differing in that the male and female contactors 23, 39' are formed to internest axially after which they are rotated in opposite directions through a small angle to lock them assembled. This locking action is accomplished by a tang 48 on the end of male contactor 23' which has an interlocking fit with a bulge 49 formed in one side of the female contactor 39'. 7

Another difference in the two embodiments resides in the fact that the twist lock connector includes a short cylindrical cap member 50 of insulation material enclosing the female contactors 39' and having openings 51 aligned with the latter contactors through which the male contactors 23 pass during the coupling and un coupling operations. Since in all other respects the two connector assemblies and their novel features correspond with those described in connection with FIGS. 1-3 it is unnecessary to repeat this description.

While the particular service cord fitting and connector herein shown and disclosed in detail is fully capable of attaining the objects and providing the advantages hereinbefore stated it is to be understood that it is merely illustrative of the presently preferred embodiment of the invention and that no limitations are intended to the detail of construction or design herein shown other than as defined in the appended claims.

I claim:

l. A service cord fitting comprising: a nonconductive main body having an entrance for an electrical service cord having a plurality of conductors, a separate contactor for each of said conductors, a plurality of threaded wells in said main body, a well sized to snugly receive the end of a respective one of said conductors and inclined acutely to the axis of a respective one of said threaded wells and opening through the inner end of the sidewall of a respective one thereof, a portion of said contactors being offset to one lateral side of each of said threaded wells, and a conductive screw seated in each of said threaded wells in pressure contact with a portion of the associated one of said contactors with the crest of its thread in pressure contact with the side of a respective one of said conductors when properly tightened in said wells.

2. A service cord fitting as defined in claim 1 characterized in that said screws and said contactors are constructed to hold said contactors immovably assembled end of said screw being enlarged and designed to bottom against said tang to limit the tightening of the screw and to anchor said contactor, assembled to said main body.

4. A service cord fitting as defined in claim 1 characterized in that the threads on said screws are effective to cut through the insulation on said conductors and to penetrate the surface of the conductor itself as the screws approach their respective fully tightened condition.

5. A service cord fitting as defined in claim 4 characterized in that said contactor is a substantially rigid non-flexibe male contactor.

6. A service cord fitting as defined in claim 4 characterized in that said contactor includes a resilient female contact portion adapted to flex if necessary to accommodate a rigid male contactor.

7. A service cord fitting as defined in claim 1 including a pair of said fittings with one thereof having male contactors and the other thereof having female contactors positioned to intemest with said male contactors.

8. A service cord fitting as defined in claim 7 characterized in that said male and female contactors are designed to lock together after internesting assembly by relative rotary movement about their aligned axes.

9. A replacement service cord connector comprising a nonconductive main body having a pair of threaded wells, a pair of conductor seating wells closely spaced to said threaded wells and acutely inclined thereto with their inner ends opening through the sidewall of a respective one of said threaded wells, said conductor seating wells each accommodating one of a pair of insulated service cord conductors, a rigid male contactor for each threaded well mounted in said main body closely beside one lateral side of each of said threaded wells and having a perforated tang overlying the outer end of a respective one of said threaded wells, a metal screw passing through said tangs and into said threaded wells efi'ective when tightened to anchor said contactors immovably assembled to said main-body with its thread crest cutting through the conductor insulation and penetrating into conductors installed in said conductor wells to anchor the same in place while making firm electrical contact therewith.

10. A connector as defined in claim 9 characterized in the provision of cap means for said main body and including means for holding the same assembled across the screw receiving end of said threaded wells.

11. A connector as defined in claim 9 characterized in that said main body includes an endwall crosswise of the inner ends of said threaded wells and formed with openings through which said male contactors project. i =8 l t t UNITED STATES PATENT OFFK E CERTIFEQATE 9F EGRREC'HUN I v t r( Marvin A. Clark It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

On thecover sheet insert The portion of the term of Signed and sealed this 24th day of December 1974.

(SEAL) Attest:

MCCOY M. GIBSON JR. c. MARSHALL DANN Attesting Officer Commissioner of Patents .Patent No. 3.750.089, Dated July 31, 1973 this patent subsequent to May 18, 1988,has been disclaimed.

FORM po'wso (10459) I USCOMM-DC wave-ps9 v I r54 GOVERNMENT PRINTING OFFICE: 959 0'356'33t 

1. A service cord fitting comprising: a nonconductive main body having an entrance for an electrical service cord having a plurality of conductors, a separate contactor for each of said conductors, a plurality of threaded wells in said main body, a well sized to snugly receive the end of a respective one of said conductors and inclined acutely to the axis of a respective one of said threaded wells and opening through the inner end of the sidewall of a respective one thereof, a portion of said contactors being offset to one lateral side of each of said threaded wells, and a conductive screw seated in each of said threaded wells in pressure contact with a portion of the associated one of said contactors with the crest of its thread in pressure contact with the side of a respective one of said conductors when properly tightened in said wells.
 2. A service cord fitting as defined in claim 1 characterized in that said screws and said contactors are constructed to hold said contactors immovably assembled to said main body when tightened to make electrical contact with one of said conductors.
 3. A service cord fitting as defined in claim 1 characterized in that said contactors have a perforated tang extending across the outer end of a respective one of said threaded wells with the perforation in registry therewith to receive one of said screws, and the outer end of said screw being enlarged and designed to bottom against said tang to limit the tightening of the screw and to anchor said contactor assembled to said main body.
 4. A service cord fitting as defined in claim 1 characterized in that the threads on said screws are effective to cut through the insulation on said conductors and to penetrate the surface of the conductor itself as the screws approach their respective fully tightened condition.
 5. A service cord fitting as defined in claim 4 characterized in that said contactor is a substantially rigid non-flexibe male contactor.
 6. A service cord fitting as defined in claim 4 characterized in that said contactor includes a resilient female contact portion adapted to flex if necessary to accommodate a rigid male contactor.
 7. A sErvice cord fitting as defined in claim 1 including a pair of said fittings with one thereof having male contactors and the other thereof having female contactors positioned to internest with said male contactors.
 8. A service cord fitting as defined in claim 7 characterized in that said male and female contactors are designed to lock together after internesting assembly by relative rotary movement about their aligned axes.
 9. A replacement service cord connector comprising a nonconductive main body having a pair of threaded wells, a pair of conductor seating wells closely spaced to said threaded wells and acutely inclined thereto with their inner ends opening through the sidewall of a respective one of said threaded wells, said conductor seating wells each accommodating one of a pair of insulated service cord conductors, a rigid male contactor for each threaded well mounted in said main body closely beside one lateral side of each of said threaded wells and having a perforated tang overlying the outer end of a respective one of said threaded wells, a metal screw passing through said tangs and into said threaded wells effective when tightened to anchor said contactors immovably assembled to said main body with its thread crest cutting through the conductor insulation and penetrating into conductors installed in said conductor wells to anchor the same in place while making firm electrical contact therewith.
 10. A connector as defined in claim 9 characterized in the provision of cap means for said main body and including means for holding the same assembled across the screw receiving end of said threaded wells.
 11. A connector as defined in claim 9 characterized in that said main body includes an endwall crosswise of the inner ends of said threaded wells and formed with openings through which said male contactors project. 